The three-day festival was billed as a three-day "neon" sleepover in Vegas. Several big name performers were involved, including Sam Hunt, Eric Church and Lee Brice.

The crowd at the Jason Aldean show was estimated to be around 35,000.

Jason Aldean, who ran off stage when the gunfire began, took to social media to express his shock and horror at what had taken place: "I still don't know what to say but wanted to let everyone know that Me and my Crew are safe. My Thoughts and prayers go out to everyone involved tonight. It hurts my heart that this would happen to anyone who was just coming out to enjoy what should have been a fun night."

Singer Niall Horan called what happened on the Strip a "terrible tragedy" and said that his "thoughts are with the victims and families." His One Direction bandmate Harry Styles echoed the same sentiment and said the shooting was "heartbreaking news."

Thoughts are with the victims and families of this terrible tragedy in Vegas .